The benefits of computer-aided diagnosis (CAD) in radiology in general, and particularly in mammography, are widely recognized. To date, there has been considerable effort directed toward computer-aided methods that assist the diagnostician to correctly and efficiently identify problem areas detected in a mammography image and to improve the accuracy with which diagnoses are made using this information.
There have been a number of initiatives directed toward diagnostic image management, presentation, and delivery. One initiative is the DICOM (Digital Imaging and Communications in Medicine) standard, developed to effectively manage the potentially large amounts of patient data that are now available from a range of diagnostic and imaging systems. Developed and maintained as a joint effort through the National Electrical Manufacturers Association, the DICOM data interchange standard has the goal of providing a common framework for acquisition, transmission, archival, retrieval, and presentation of medical images and related patient data from a variety of imaging modalities and environments. Benefits from DICOM conformance are believed to include interoperability of equipment from different manufacturers so that patient data, once obtained, can be accessible for display, printing, diagnostic assessment, and storage, without requiring proprietary systems and software. For example, DICOM conformance allows mammography images from any of a number of different types of equipment to be processed on a single Computer-Aided Diagnosis (CAD) system. Results from the CAD system can then be stored and used for viewing or presentation by other conforming systems.
The DICOM standard defines data structures, communication protocols, and interaction models for data transfer between systems. While it is widely viewed that DICOM conformance offers considerable benefit to equipment manufacturers and systems providers as well as to medical professionals and the patients they serve, achieving conformance and compatibility between systems has proven to be a challenge. Even though efforts at conformance have been underway, seamless interoperability is not guaranteed because different vendors can implement different parts of the same large standard.
In an effort to facilitate DICOM inter-operability, an ongoing industry initiative entitled Integrating the Healthcare Enterprise (IHE) was formed. The IHE effort has helped to delineate how portions of the DICOM standard can be implemented in practice, so that the necessary common framework for information interchange can be developed in a coordinated and timely manner.
There is particular interest in DICOM compliance from vendors who provide mammographic CAD systems. These systems accept digital image input data, typically scanned from X-ray films, and perform various algorithmic operations on the images obtained in order to help automate the identification of lesions and other structural abnormalities within the breast tissue. Some examples of mammography CAD systems are described in U.S. Pat. No. 5,729,620 entitled “Computer-Aided Diagnosis System and Method” to Wang, and U.S. Pat. No. 6,650,766 entitled “Method For Combining Automated Detections From Medical Images With Observed Detections Of A Human Interpreter” to Rogers et al. DICOM compliance for CAD systems should provide system compatibility, and also support the overall CAD processing workflow.
Digital mammography CAD systems are gaining increasing acceptance and capable digital display and image assessment techniques are continually being developed. As part of this process, there are corresponding changes to conventional techniques and practices for mammography. One area of digital mammography system architects is to provide a workflow schema and support tools that allow practitioners to take more complete advantage of digital display and diagnosis capabilities. In making the transition from display film to display screen, for example, radiologists have certain expectations and behavior patterns that work best for them and that help to systematize their work for efficiency and effectiveness. One of the design challenges is to allow a smooth transition to digital imaging, without compromising the efficiency of existing, familiar methods and to make new capabilities easier to use.
There has been interest in providing a user interface and utilities that are suited for diagnostic imaging. The following references provide some examples.
U.S. Pat. No. 6,734,880 entitled “User Interface for a Medical Informatics System” to Chang et al. describes use of a screen layout for image browsing modeled after that traditionally used for analog film imaging, with added pan and zoom features.
U.S. Pat. No. 6,925,200 entitled “Graphical User Interface for Display of Anatomical Information” to Wood et al. describes an X-ray imaging apparatus with a display screen that provides various arrangements along with different types of markers for identifying specific regions of interest.
U.S. Pat. No. 5,987,345 entitled “Method and System for Displaying Medical Images” to Engelmann et al. describes an image display system that can have multiple terminals for control and display purposes.
U.S. Patent Published Application No. 2004/0102689 entitled “Workflow for Computer Aided Detection” by Metz et al. describes a workflow arrangement associated with the DICOM imaging architecture.
U.S. Patent Published Application No. 2003/0026503 entitled “Workstation Interface for Use in Digital Mammography and Associated Methods” by Kallergi et al. describes a user interface having tools for specifying CAD processing operations and viewing results.
U.S. Pat. No. 6,970,587 entitled “Use of Computer-Aided Detection System Outputs in Clinical Practice” to Rogers et al. describes CAD processing techniques for applying masks, determining thresholds, and performing other imaging operations for mammography systems.
U.S. Patent Published Application No. 2004/0247166 entitled “Method, System and Computer Readable Medium for an Intelligent Search Workstation for Computer Assisted Interpretation of Medical Images” by Giger et al. describes automated utilities for assessing mammography images and classifying abnormal structures in these images.
U.S. Patent Published Application No. 2004/0122790 entitled “Computer-Assisted Data Processing System and Method Incorporating Automated Learning” by Walker et al. describes a method for improving results from computer-assisted diagnostic imaging algorithms using feedback from medical professionals.
While the references listed above provide some measure of support for diagnostic workflow, there is considerable room for improvement.
One challenge recognized by Applicants relates to adapting digital display technology to familiar tools and practices used by the diagnostician. That is, display utilities should conform to existing practices and procedures where possible, rather than forcing a user to adapt to a new diagnostic workflow in order to suit the design of the display system. Traditionally, diagnosticians are used to handling film images and have developed expertise for maximizing accuracy from reading these analog images. Where there are new tools and capabilities with digital imaging systems for Computer-Aided Diagnostics, these should be integrated with familiar patterns of operation where possible. The workflow for a digital diagnostic system should emulate the workflow that is currently used for assessing analog films.
Other challenges relate to the need to correlate information obtained from different medical imaging modalities, including not only x-ray images, but also images from magnetic resonance (MR) systems, ultrasound apparatus, and other medical imaging devices. Inconsistent image processing and display techniques used for these different technologies make it difficult for the diagnostician to use their combined results effectively.
Thus, there is a need for a display platform that supports physician workflow for digital mammography and other medical imaging modalities, that provides improved consistency for correlation of images obtained from different sources and at different times, and that takes advantage of digital capabilities to provide high-resolution image display having suitable image quality for improving the effectiveness of screening and diagnosis.